A375kV/μs Common-Mode Transient Immunity Digital Signal Isolator with High Reliability

To address the high common-mode transient immunity(CMTI) requirements of emerging industries, this study proposes a high CMTI, high reliability digital signal isolator. First, Manchester encoding technology is adopted to embed the carrier clock and input signal into the same data stream for transmission; Second, Common-mode current elimination(CMCE) technology is employed to suppress common-mode noise during data reception; Third, high CMTI amplifier circuit with dual feedback is combined to amplify the differential-mode signal to the power rail, thereby further mitigating the interference of common-mode noise on the differential-mode signal. Finally, decoding circuit employs an edge-triggered oscillator for clock recovery and generates a calibration signal to demodulate the output data. Measured results show that when a common-mode transient voltage with a change rate of 375kV/μs within 0.96ns, and an amplitude of 1kV is generated, the output can correctly demodulate the input data. The data transmission rate is 5MHz, and when the transmission rate is 1MHz, the power consumption is 2.9mA, meeting the application requirements of emerging fields.